List of all R2R DAC

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HpW

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Joined 2002
hpw-works.com
analog_sa said:
Perhaps this list will be more useful if the chip and discrete solutions are kept separate, as there are only a handful of discretes and hundreds of chip based dacs.
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Exactly = PCM 1704 :rolleyes: , while still love my WADIA 27 spline based interpolation sound (tube alike) than this pre/post ringing AKM/ESS and so one.

Also the soldered R/2/R stuff will get humid and poisoned over time with a guarantee of oxidation and leakage. In other words a thin laser trimmed film based substrate is hard to beet.

Hp
 
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MarcelvdG

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Joined 2003
According to the TDA1541 datasheet, page 5: "True 16-bit performance is achieved by each channel using three 2-bit active dividers operating on the dynamic element matching principle, in combination with a 10-bit passive current-divider, based on emitter scaling."

TDA1541 Datasheet pdf - Dual 16-bit DAC - Philips

I'm not sure why they call a circuit based on emitter scaling a passive current divider, but it sounds to me like the TDA1541 is based on scaled current sources rather than R2R networks. It might use an R-2R network to divide the current between the sources for the lower ten bits, though, depending on how they implemented that "10-bit passive current-divider, based on emitter scaling".

The PCM1704 indeed has R2R networks according to its datasheet (page 6, left column, pcm1704.pdf ): "Two DACs are combined in a complementary arrangement to produce an extremely linear output. The two DACs share a common reference, and a common R-2R ladder for bit current sources. The R-2R ladder utilizes dual balanced current segments to ensure ideal tracking under all conditions."
 
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MarcelvdG

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Joined 2003
I just read Rudy van der Plassche's 1976 article about dynamic element matching. Apparently R-2R was a very common technique for splitting the currents in current source DACs, so chances are that Boydk and Zoran are correct and that the TDA1541 uses an R-2R network for its lower ten bits.
 
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gandolf

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Joined 2017
HpW said:
Exactly = PCM 1704 :rolleyes: , while still love my WADIA 27 spline based interpolation sound (tube alike) than this pre/post ringing AKM/ESS and so one.

Also the soldered R/2/R stuff will get humid and poisoned over time with a guarantee of oxidation and leakage. In other words a thin laser trimmed film based substrate is hard to beet.

Hp
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Not exactly understand why take the discrete R2R implemention route. To achieve even 16 bit ENOB, you need a 0.0001% resistor. Expensive but possible with integrated, laser trimmed thin film but good luck with the discrete resistors. Almost all discrete R2R DAC uses 0.01% or worse resistor that theoretically can only achieve 13 bit ENOB even if there is no noise (only non-linearity) at all.
 
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soekris

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Joined 2009
soekris.dk
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gandolf said:
Not exactly understand why take the discrete R2R implemention route. To achieve even 16 bit ENOB, you need a 0.0001% resistor. Expensive but possible with integrated, laser trimmed thin film but good luck with the discrete resistors. Almost all discrete R2R DAC uses 0.01% or worse resistor that theoretically can only achieve 13 bit ENOB even if there is no noise (only non-linearity) at all.
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Whats important for Audio is not absolute linearity, but good level linearity, so you don't need that precise resistors for a good discrete R-2R DAC, just use the Sign Magnitude principle (same as PCM63 and later parts)....
 
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